Exploratorium?s The Phenomenal Genome: Evolving Public Understanding of Genetics in the Post-Mendelian Era project addresses the increasing need to develop genomic literacy in the public at large. The explosion of genomics research over the past two decades has led to an increasingly complex picture of the determinants of human health and human phenotypes, and the applications of this research are now making their way into the clinic, the media, and the hands of consumers. The goal of this project is to create a model for increasing genomic literacy through Informal Science Education programming (ISE), creating a pathway for better decision making for the health of individuals and society at large. The Phenomenal Genome focuses on general science museum visitors and teachers of middle and high school students. The core of the Exploratorium?s approach to science education is the creation of intriguing, provocative and investigable phenomena that are experienced directly and personally through exhibits, facilitated explorations, programs, and teacher professional development. Over two years, we will develop, test, and iterate inquiry-based professional development to help teachers develop understanding and integrate the principles of contemporary genomics and genetics into their classrooms. 120 middle and high school teachers will be served during this period, and many more beyond that, as the activities and workshops developed become a regular part of our teacher professional development programming. A learning scientist specializing in teacher learning will conduct research to determine which approaches and experiences are most effective for this context, and why. In a parallel process, we will develop and test exhibits and experiences on the museum floor for museum visitors, using a similar iterative process of prototype testing with an embedded learning scientist to study visitor learning. We plan to define the approaches that work across audiences and contexts, as well as those that work best in particular contexts. Through this work, we will develop new resources for teaching and learning contemporary genomics and genetics, and identify promising practices in communicating contemporary genomics and genetics in informal spaces across audiences. We will disseminate our findings via conferences, peer-reviewed articles, and workshops for the ISE community.